Term
| how many causes of nematode infections are there? |
|
Definition
| 2. AScariasis and Hookworm disease |
|
|
Term
|
Definition
| where many people harbour many different parasites |
|
|
Term
| how many known species of nematodes are there? |
|
Definition
| 100,000 known species but there are probably 10 times more that actually exist. |
|
|
Term
t or f?
nematodes are important parasites of animals and plants? |
|
Definition
| true. they are also important in medicine and agriculture |
|
|
Term
| do nematodes look alike or different? |
|
Definition
| they look alike. the smallest one is a scaled down version of a bigger one. |
|
|
Term
| how long is the smallest nematode known? |
|
Definition
|
|
Term
| how long was the largest ever nematode recorded? |
|
Definition
| 8m long. found in the placenta of a sperm whale. it is called placentonema gigantisma. |
|
|
Term
| why are nematodes so successful? |
|
Definition
| able to survive in wide range of conditions like osmotic pressure, temp and pH. their biochemistry and physiology are very adaptable. |
|
|
Term
| what is the function of nematodes touch outer cuticle? |
|
Definition
| to withstand immune responses |
|
|
Term
| describe nematode geographical distribution |
|
Definition
| widespread, particularly in poor socieconomic conditions that facilitate transmission |
|
|
Term
| are nematode egg production high or low? |
|
Definition
| high! also the eggs can survive diverse environmental conditions |
|
|
Term
t or f?
nematodes undergo sexual reproduction? |
|
Definition
| false- they do not. However, they do undergo parthenogenisis. (growth and development of larvae without fertilisation) |
|
|
Term
| how many eggs can ascaris produce per day? |
|
Definition
|
|
Term
| how many eggs can a hookworm produce per day? |
|
Definition
|
|
Term
| who produces more eggs? ascaris or hookworm? |
|
Definition
|
|
Term
| nematode life cycles can be direct or indirect. what is needed in indirect life cycles? |
|
Definition
|
|
Term
| how many larval and moult stages are there in nematode life cycles? |
|
Definition
|
|
Term
| from the 4 larval stages which ones are infective? |
|
Definition
|
|
Term
| which stage are ascaris larvae at? |
|
Definition
| L2, thus already infective |
|
|
Term
| at which larvae stage would you find hookworms? |
|
Definition
|
|
Term
| where is an anatomically popular site for gastrointestinal helminths? |
|
Definition
| Intestines of vertebrates |
|
|
Term
| how do GI helminths get access to bodies? |
|
Definition
|
|
Term
| how are GI helminths transmitted? |
|
Definition
|
|
Term
| intestinal species are the most common helminths but are they the most pathogenic? |
|
Definition
|
|
Term
| whats the full name for ascariasis? |
|
Definition
|
|
Term
| name two hookworm species |
|
Definition
necator americanus
ancylostoma dudodenale |
|
|
Term
| where is the highest prevalence for ascaris lumbricoides? |
|
Definition
| tropical/sub tropical regions and areas with inadequate sanitation |
|
|
Term
| in A. lumbricoides are males or females bigger? |
|
Definition
females!
Males 10-30cm
Females 20-35cm |
|
|
Term
| describe the shell on A. lumbricoides eggs. |
|
Definition
|
|
Term
| how many eggs does A lumbricoides lay per day? |
|
Definition
|
|
Term
| roughly how many days incubation do the larvae require to develop? |
|
Definition
|
|
Term
| how long can A lumbricoides eggs remain infective for? |
|
Definition
| several month to several years |
|
|
Term
| how is ascaris lumbricoides spread? |
|
Definition
| ingestion of infective eggs - this is known as its direct life cycle |
|
|
Term
| in which part of the human body do ascaris lumbricoides eggs hatch? |
|
Definition
| small intestine. they release L2 larvae. |
|
|
Term
| after l2 larvae hatch what do they do? |
|
Definition
| penetrate intestinal wall, enter blood stream and migrate to liver, heart and lungs. this takes approx 1-7 days. |
|
|
Term
| what happens to l2 larvae in the lungs? |
|
Definition
| they moult twice to form L4 Larvae |
|
|
Term
| after becoming L4 larvae in lungs where do a lumbricoides proceed? |
|
Definition
| burrow out of blood vessels and enter bronchioles migrating up trachea. they enter the throat, are swallowed and end up in s.intestine where they mature into adults. |
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